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<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<script>
// 多维数组    一维数组   二维数组
var a = [ [10, 20], [20, 30, 40], [10] ]
for(var t of a){
    for(tt of t){
        console.log(tt)
    }
}
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</script>
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